OFA tweet-targets senators on guns

4/24/13 6:09 PM EDT

Pro-Obama group Organizing for Action is using Twitter to target 11 senators who voted against expanded background checks for gun buyers last week, including the four Democrats.

The group that grew out of the president's campaign is urging the senators' constituents to click on a new tool that automatically generates tweets.

".@SenatorHeitkamp 94% of North Dakotans support background checks, but you voted against them. Why? #WeWillBeHeard," reads the one for Sen. Heidi Heitkamp (D-N.D.).

The other Democrats are Sens. Mark Begich of Alaska, Mark Pryor of Arkansas, and Max Baucus of Montana. The Republican targets are Sens. Saxby Chambliss and Johnny Isakson of Georgia, Chuck Grassley of Iowa, Dean Heller of Nevada, Kelly Ayotte of New Hampshire, Rob Portman of Ohio, and Jeff Flake of Arizona.

OFA had said last week that it also planned to go after the no-voters with online ads, letter-writing campaigns and rallies.